Is it possible to have intercooler piping too large for your intake system?
I know the whole deal with exhaust, that if it's too small, it's restrictive, too large and the gasses bounce around. The only pictures I could find were from an [&o]Integra site.




The next step up from the KO3S I have now seems to be a GT28**, which from what I understand will need larger intake piping, like 3". However, I will be doing an FMIC when I do my timing belt this summer, and don't plan on upgrading my turbo till next summer. A few dollars is something I'd rather waste than a few horsepower if I need to run 2.25" piping now, but was curious on what sort of input everyone had on larger intercooler piping?
And should I be referring to this as tubing? I always confuse the terms.

 

First, that chart is for NA cars, NOT FI cars, that doenst apply here. With a turbo car you want no restrictions on the exhaust, so the bigger the better. However at a certian point, you dont gain anything but noise for going larger.

Ic piping depends on the amount of flow a turbo is pushing. The more airflow the larger the piping. A ko3 only need 2" piping and a gt28XX turbo wont need anything larger than 2.25" all around. You can use 2.25" on a stock turbo, but you will see some very minor pressure drop (maybe 1-2psi depending on the ic core size).

 

i have 2.5" piping, and i'm going to do the gt28 rig this spring, should work out perfectly

 

a gt28.....? Thats a family name and there are a few turbos in that fam.

gt28r - gt2560r
gt28rs - gt2860r
gt2871r
gt2876r - gt25/40r

Not to mention the T25 .64 and .86 housings.

 

Yeah, I was using the exhaust diagrams as a means of showing proper flow vs. improper flow as it related to NA cars on the rear end of things, but was wondering if it applied to the front end of a turbo car. If there is a 1-2 psi pressure drop, than it sounds like it would.
CincyTT, you've been nothing but good help for every engine related question I have asked, thank you for helping out.
Russian, did you notice any PSI issues with the 2.5"? How was the fitment on the passenger side when avoiding the horn and such with the larger piping?

 

i had 2.5" piping and i thought i have a crazy pressure drop it dropped 7 psi. it just so happens that i had a major boost leak which i was unaware off. i didnt figure that out until after i changed my piping to 2" thinking that was the problem. so i never really got to see how much psi drop it was with 2.5" but it did fit fine i didnt really have too many problems